2024
2024
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Record 397 of
Title:Static spectroscopic ellipsometer based on division-of-amplitude polarization demodulation
Author Full Names:Li, Siyuan; Deng, Zhongxun; Quan, Naicheng; Zhang, ChunminSource Title:OPTICS COMMUNICATIONSLanguage:EnglishDocument Type:ArticleKeywords Plus:MODULATORSAbstract:Theoretical and experimental demonstrations of a static spectroscopic ellipsometer are presented. It uses a linear polarizer for generating polarization states to interact with the sample, and three non-polarization beam splitters incorporating four achromatic quarter waveplate/linear analyzer pairs for analyzing the polarization states after the interaction. Compared to previous instruments, the most significant advantage of the described model is that it can obtain the spectral ellipsometric parameters with the same spectral resolution as the spectrometer in the system by a single snapshot.Addresses:[Li, Siyuan] Chinese Acad Sci, Xian Inst Opt & Precis Mech, Key Lab Spectral Imaging Technol CAS, Xian, Peoples R China; [Li, Siyuan] Univ Chinese Acad Sci, Beijing, Peoples R China; [Deng, Zhongxun] Shenmu Vocat & Tech Coll, Shenmu, Peoples R China; [Quan, Naicheng] Xian Univ Technol, Sch Mat Sci & Engn, Xian, Peoples R China; [Zhang, Chunmin] Xi An Jiao Tong Univ, Sch Sci, Xian 710049, Peoples R ChinaAffiliations:Chinese Academy of Sciences; Xi'an Institute of Optics & Precision Mechanics, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Xi'an University of Technology; Xi'an Jiaotong UniversityPublication Year:2024Volume:552Article Number:130115DOI Link:http://dx.doi.org/10.1016/j.optcom.2023.130115數(shù)據(jù)庫ID（收錄號）:WOS:001110587300001 -
Record 398 of
Title:Luminescence properties of ZnSxO1-x:Ce3+ phosphors with tunable short fluorescence lifetime
Author Full Names:Xing, Xue; Cao, Weiwei; Wu, Zhaoxin; Bai, Xiaohong; Gao, Jiarui; Liang, Xiaozhen; Wang, Bo; Wang, Chao; Shi, Dalian; Lv, Linwei; Bai, YonglinSource Title:MATERIALS LETTERSLanguage:EnglishDocument Type:ArticleAbstract:Fluorescence lifetime of phosphors is a critical index in the field of high energy physics and astrophysical detection. A series of ZnSxO1-x:0.05Ce(3+) phosphors with tunable short fluorescence lifetime were prepared by performing high temperature solid state reaction method. The phosphors exhibited two mixed phases consisting of the hexagonal phase ZnO and the hexagonal phase ZnS. They are spherical and the average particle size is 2.24 mu m. As the component content of the ZnS in ZnSxO1-x:0.05Ce(3+) phosphors varies, the emission wavelength can be tuned from 448 nm to 495 nm, the short fluorescence lifetime can be tuned within the range of 6 mu s-200 mu s. By performing exponential fitting, we obtained the equation for the variation of fluorescence lifetime of ZnSxO1-x:0.05Ce(3+) phosphors with ZnS fraction.Addresses:[Xing, Xue; Cao, Weiwei; Bai, Xiaohong; Gao, Jiarui; Liang, Xiaozhen; Wang, Bo; Wang, Chao; Shi, Dalian; Lv, Linwei; Bai, Yonglin] Chinese Acad Sci, Xian Inst Opt & Precis Mech, Key Lab Space Sci Low Light Level Detect Technol, Xian 710119, Shaanxi, Peoples R China; [Xing, Xue; Wu, Zhaoxin] Xi An Jiao Tong Univ, Sch Elect Sci & Engn, Xian 710049, Shaanxi, Peoples R China; [Xing, Xue; Cao, Weiwei] Univ Chinese Acad Sci, Beijing 100049, Peoples R China; [Cao, Weiwei] Xi An Jiao Tong Univ, Key Lab Informat Photon Tech, Xian 710049, Shaanxi, Peoples R ChinaAffiliations:Chinese Academy of Sciences; Xi'an Institute of Optics & Precision Mechanics, CAS; Xi'an Jiaotong University; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Xi'an Jiaotong UniversityPublication Year:2024Volume:355Article Number:135472DOI Link:http://dx.doi.org/10.1016/j.matlet.2023.135472數(shù)據(jù)庫ID（收錄號）:WOS:001106393000001 -
Record 399 of
Title:Speckle-correlation-based non-line-of-sight imaging under white-light illumination
Author Full Names:Zhou, Meiling; Zhang, Yang; Wang, Ping; Li, Runze; Peng, Tong; Min, Junwei; Yan, Shaohui; Yao, BaoliSource Title:OPTICS AND LASER TECHNOLOGYLanguage:EnglishDocument Type:ReviewKeywords Plus:RECONSTRUCTION; CORNERSAbstract:Non-line-of-sight (NLOS) imaging is attracting extensive attention due to its ability to establish the objects hidden from the direct line-of-sight, which prompts potential applications in autonomous driving, robotic vision, biomedical imaging, and other domains. Various NLOS imaging techniques have been successively demonstrated. In this paper, we propose a speckle-correlation-based method to achieve NLOS imaging under white-light illumination. In the proposed method, we process the raw speckle pattern by incorporating the conventional speckle correlation imaging (SCI) with the Zernike polynomial fitting, named ZPF-SCI method, to enhance the performance of the calculated autocorrelation, a key step to achieve optimal image quality. Experimental results demonstrate that our method is effective even in the presence of ambient light, which circumvents the limitation of the conventional SCI that has to be performed in a darkroom. Furthermore, the proposed ZPF-SCI method is insensitive to the angle that the detector deviates from the vertical plane of the optical axis. The quality of the reconstructed image is still acceptable even if the deviation angle reaches 8 degrees. These superiorities facilitate the practical application of the method.Addresses:[Zhou, Meiling; Zhang, Yang; Wang, Ping; Li, Runze; Peng, Tong; Min, Junwei; Yan, Shaohui; Yao, Baoli] Chinese Acad Sci, State Key Lab Transient Opt & Photon, Xi An Inst Opt & Precis Mech, Xian 710119, Peoples R China; [Zhang, Yang; Yao, Baoli] Univ Chinese Acad Sci, Beijing 100049, Peoples R China; [Yao, Baoli] Qingdao Marine Sci & Technol Ctr, Qingdao 266200, Peoples R China; [Wang, Ping] Xi An Jiao Tong Univ, Sch Life Sci & Technol, Key Lab Biomed Informat Engn, Minist Educ, Xian 710049, Peoples R ChinaAffiliations:State Key Laboratory of Transient Optics & Photonics; Chinese Academy of Sciences; Xi'an Institute of Optics & Precision Mechanics, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Xi'an Jiaotong UniversityPublication Year:2024Volume:170Article Number:110231DOI Link:http://dx.doi.org/10.1016/j.optlastec.2023.110231數(shù)據(jù)庫ID（收錄號）:WOS:001101007000001 -
Record 400 of
Title:HQ-I2IT: Redesign the optimization scheme to improve image quality in CycleGAN-based image translation systems
Author Full Names:Zhang, Yipeng; Hu, Bingliang; Huang, Yingying; Gao, Chi; Yin, Jianfu; Wang, QuangSource Title:IET IMAGE PROCESSINGLanguage:EnglishDocument Type:ArticleAbstract:The image-to-image translation (I2IT) task aims to transform images from the source domain into the specified target domain. State-of-the-art CycleGAN-based translation algorithms typically use cycle consistency loss and latent regression loss to constrain translation. In this work, it is demonstrated that the model parameters constrained by the cycle consistency loss and the latent regression loss are equivalent to optimizing the medians of the data distribution and the generative distribution. In addition, there is a style bias in the translation. This bias interacts between the generator and the style encoder and visually exhibits translation errors, e.g. the style of the generated image is not equal to the style of the reference image. To address these issues, a new I2IT model termed high-quality-I2IT (HQ-I2IT) is proposed. The optimization scheme is redesigned to prevent the model from optimizing the median of the data distribution. In addition, by separating the optimization of the generator and the latent code estimator, the redesigned model avoids error interactions and gradually corrects errors during training, thereby avoiding learning the median of the generated distribution. The experimental results demonstrate that the visual quality of the images produced by HQ-I2IT is significantly improved without changing the generator structure, especially when guided by the reference images. Specifically, the Frechet inception distance on the AFHQ and CelebA-HQ datasets are reduced from 19.8 to 10.2 and from 23.8 to 17.0, respectively. In this work, it is demonstrated that the cycle consistency loss and latent regression loss in CycleGAN-based image translation models can be detrimental to image quality. The optimization scheme of CycleGAN-based image translation systems is redesigned and a new translation model named HQ-I2IT is proposed. Experiments demonstrate that the proposed method can significantly improve image quality and translation accuracy.imageAddresses:[Zhang, Yipeng; Hu, Bingliang; Huang, Yingying; Gao, Chi; Yin, Jianfu; Wang, Quang] Chinese Acad Sci, Xian Inst Opt & Precis Mech, Key Lab Spectral Imaging Technol, 17 Informat Ave, Xian 710119, Shaanxi, Peoples R China; [Zhang, Yipeng; Hu, Bingliang; Huang, Yingying; Gao, Chi; Yin, Jianfu; Wang, Quang] Key Lab Biomed Spect Xian, Xian, Shaanxi, Peoples R China; [Zhang, Yipeng; Huang, Yingying; Gao, Chi; Yin, Jianfu] Univ Chinese Acad Sci, Sch Optoelect, Beijing, Peoples R ChinaAffiliations:Chinese Academy of Sciences; Xi'an Institute of Optics & Precision Mechanics, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CASPublication Year:2024Volume:18Issue:2Start Page:507End Page:522DOI Link:http://dx.doi.org/10.1049/ipr2.12965數(shù)據(jù)庫ID（收錄號）:WOS:001087975200001 -
Record 401 of
Title:Multispectral Image Quality Improvement Based on Global Iterative Fusion Constrained by Meteorological Factors
Author Full Names:Shi, Yuetian; Fu, Bin; Wang, Nan; Chen, Yaxiong; Fang, JieSource Title:COGNITIVE COMPUTATIONLanguage:EnglishDocument Type:ArticleAbstract:It has been proven that the refractive index is related to meteorological parameters in physics. The temperature changes the atmospheric and lens refractive indices, resulting in image degradation. Image restoration aims to recover the sharp image from the degraded images. It is also the basis of many computer vision tasks. A series of methods have been explored and used in this area. Sometimes, meteorological factors cause image degradation. Most of the existing image restoration methods do not consider meteorological factors' influence on image degradation. How meteorological factors affect image quality is not yet known. A multispectral image dataset with corresponding meteorological parameters is presented to solve the problem. We propose a novel multispectral image restoration algorithm using global iterative fusion. The proposed method firstly enhances image edge features through spatial filtering. Then, the Gaussian function is used to constrain the weights between each channel in the image. Finally, a global iterative fusion method is used to fuse image spatial and spectral features to obtain an improved multispectral image. The algorithm explores the impact of meteorological factors on image quality. It considers the impact of atmospheric factors on image quality and incorporates it into the image restoration process. Extensive experimental results illustrate that the method achieves favorable performance on real data. The proposed algorithm is also more robust than other state-of-the-art algorithms. In this paper, we present an algorithm for improving the quality of multispectral images. The proposed algorithm incorporates the influence of meteorological parameters into the image restoration method to better describe the relationship between different spectral channels. Extensive experiments are conducted to validate the effectiveness of the algorithm. Additionally, we investigate the impact of near-surface meteorological parameters on multispectral image quality.Addresses:[Shi, Yuetian; Wang, Nan] Chinese Acad Sci, Key Lab Spectral Imaging Technol CAS, Xian Inst Opt & Precis Mech, Xian 710119, Shaanxi, Peoples R China; [Shi, Yuetian; Wang, Nan] Univ Chinese Acad Sci, Beijing 100049, Peoples R China; [Fu, Bin] SenseTime Res, Shenzhen 518000, Guangdong, Peoples R China; [Chen, Yaxiong] Wuhan Univ Technol, Sch Comp & Artificial Intelligence, Wuhan 430000, Hubei, Peoples R China; [Fang, Jie] Xian Univ Posts & Telecommun, Sch Telecommun & Informat Engn, Xian 710119, Peoples R China; [Fang, Jie] Corp Shaanxi Wukong Clouds Informat & Technol, Xian 710000, Shaanxi, Peoples R ChinaAffiliations:Chinese Academy of Sciences; Xi'an Institute of Optics & Precision Mechanics, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Wuhan University of Technology; Xi'an University of Posts & TelecommunicationsPublication Year:2024Volume:16Issue:1Start Page:404End Page:424DOI Link:http://dx.doi.org/10.1007/s12559-023-10207-7數(shù)據(jù)庫ID（收錄號）:WOS:001085807800001 -
Record 402 of
Title:Gain-switched 3 μm dysprosium-doped fluoride fiber laser pumped at 1.7 μm
Author Full Names:Xiao, Yang; Xiao, Xusheng; He, Chunjiang; He, Yuxuan; Guo, HaitaoSource Title:OPTICS AND LASER TECHNOLOGYLanguage:EnglishDocument Type:ArticleKeywords Plus:WATT-LEVEL; HIGH-ENERGY; YAG LASERAbstract:To the best of our knowledge, we demonstrated a gain-switched 3 mu m dysprosium-doped fluoride fiber laser pumped by a 1706.5 nm pulsed thulium-doped fiber master oscillator power amplifier for the first time. The maximum average power of the 3 mu m pulsed laser was 50 mW with a slope efficiency of 12.3%, a repetition rate of 100 kHz, and a pulse width of 283 ns. This work exhibits the potential of 1.7 mu m pulse pumped dysprosiumdoped fluoride fiber laser as a platform for developing pulsed sources in the 3 mu m region.Addresses:[Xiao, Yang; Xiao, Xusheng; He, Yuxuan; Guo, Haitao] Chinese Acad Sci, State Key Lab Transient Opt & Photon, Xian Inst Opt & Precis Mech, Xian 710119, Shaanxi, Peoples R China; [Xiao, Yang; Xiao, Xusheng; He, Yuxuan; Guo, Haitao] Univ Chinese Acad Sci, Ctr Mat Sci & Optoelect Engn, Beijing 100049, Peoples R China; [He, Chunjiang] Harbin Engn Univ, Qingdao Innovat & Dev Base, Qingdao 266500, Peoples R ChinaAffiliations:Chinese Academy of Sciences; Xi'an Institute of Optics & Precision Mechanics, CAS; State Key Laboratory of Transient Optics & Photonics; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Harbin Engineering UniversityPublication Year:2024Volume:169Article Number:110162DOI Link:http://dx.doi.org/10.1016/j.optlastec.2023.110162數(shù)據(jù)庫ID（收錄號）:WOS:001096616400001 -
Record 403 of
Title:Blind deep-learning based preprocessing method for Fourier ptychographic microscopy
Author Full Names:Wu, Kai; Pan, An; Sun, Zhonghan; Shi, Yinxia; Gao, WeiSource Title:OPTICS AND LASER TECHNOLOGYLanguage:EnglishDocument Type:ArticleKeywords Plus:IMAGE; ALGORITHM; PHASE; RECONSTRUCTION; TRANSFORMATION; NETWORKAbstract:Fourier ptychographic microscopy (FPM) is a technique for tackling the trade-off between the resolution and the imaging field of view by combining the techniques from aperture synthesis and phase retrieval to estimate the complex object from a series of low-resolution intensity images captured under angle-varied illumination. The captured images are commonly corrupted by multiple noise, leading to the degradation of the reconstructed image quality. Typically speaking, the noise model and noise level of the experimental images are unknown, and the traditional image denoising methods have limited effect. In this paper we model the FPM forward imaging process corrupted by noise and divide the noise in the captured images into two parts: the signal-dependent part and the signal-independent part. Based on the noise model we propose a novel blind deep-learning based Fourier ptychographic microscopy preprocessing method, termed BDFP, for removing these two components of noise. First, from a portion of the captured low-resolution images, a set of blocks corresponding to the smooth area of the object are extracted to model signal-independent noise. Second, under the assumption that the signal-dependent noise follows a Poisson distribution, we add Poisson noise and signal-independent noise blocks to clean images to form a paired training dataset, which is then used for training a deep convolutional neural network (CNN) model to reduce both signal-dependent noise and signal-independent noise. The proposed blind preprocessing method, combining with typical FPM reconstruction algorithms, is tested on simulated data and experimental images. Experimental results show that our preprocessing method can significantly reduce the noise in the captured images and bring about effective improvements in reconstructed image quality.Addresses:[Wu, Kai; Pan, An; Sun, Zhonghan; Shi, Yinxia; Gao, Wei] Chinese Acad Sci, Xian Inst Opt & Precis Mech, Xian 710119, Peoples R China; [Wu, Kai; Shi, Yinxia] Univ Chinese Acad Sci, Beijing 100049, Peoples R ChinaAffiliations:Chinese Academy of Sciences; Xi'an Institute of Optics & Precision Mechanics, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CASPublication Year:2024Volume:169Article Number:110140DOI Link:http://dx.doi.org/10.1016/j.optlastec.2023.110140數(shù)據(jù)庫ID（收錄號）:WOS:001159160100001 -
Record 404 of
Title:Secure FSO communication based on optical frequency-hopping technology using delay interferometers
Author Full Names:Wang, Jian; Jin, Ya; Xie, Zhuang; Chen, Yinfang; Liu, Yu; Zhu, NinghuaSource Title:OPTICS COMMUNICATIONSLanguage:EnglishDocument Type:ArticleKeywords Plus:TRANSMISSIONAbstract:-A novel optical frequency-hopping (OFH) scheme using optical delay interferometers (DI) is proposed and demonstrated for secure transmission in free space. By performing carrier suppression modulation on the light wave emitted by the laser and connecting the phase modulator (PM) and DI in series, the conversion of the light wave modulated by the Mach-Zehnder modulator (MZM) from phase modulation to intensity modulation can be realized, and finally output the desired optical frequency-shift-keying (OFSK) carrier signal. Meanwhile, by controlling the positions of the frequencies of the positive and negative first-order sideband light waves on the DI frequency response curve, the OFSK signals output by the two ports of the DI can be complemented in the time domain. For the proposed OFH scheme, we carried out simulation experiments of 5 km free-space link transmission and back-to-back transmission with a communication rate of 10 Gbps, and the simulation results proved the feasibility of the scheme. Additionally, we also analyze the security performance of the proposed scheme and give the security space based on the eavesdropping probability.Addresses:[Wang, Jian; Jin, Ya; Chen, Yinfang; Liu, Yu; Zhu, Ninghua] Chinese Acad Sci, Inst Semicond, State Key Lab Integrated Optoelect, Beijing 100083, Peoples R China; [Wang, Jian; Jin, Ya; Liu, Yu; Zhu, Ninghua] Univ Chinese Acad Sci, Beijing 100049, Peoples R China; [Xie, Zhuang] Chinese Acad Sci, Xian Inst Opt & Precis Mech, Xian 710119, Peoples R ChinaAffiliations:Chinese Academy of Sciences; Institute of Semiconductors, CAS; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS; Chinese Academy of Sciences; Xi'an Institute of Optics & Precision Mechanics, CASPublication Year:2024Volume:550Article Number:129939DOI Link:http://dx.doi.org/10.1016/j.optcom.2023.129939數(shù)據(jù)庫ID（收錄號）:WOS:001086887600001 -
Record 405 of
Title:Ultrahigh sensitivity terahertz refractive index sensor based on four-inscribed hole defect photonic crystal structure
Author Full Names:Wen, Jin; Sun, Wei; Liang, Bozhi; He, Chenyao; Xiong, Keyu; Wu, Zhengwei; Zhang, Hui; Yu, Huimin; Wang, QianSource Title:MICROWAVE AND OPTICAL TECHNOLOGY LETTERSLanguage:EnglishDocument Type:ArticleKeywords Plus:FIBERAbstract:We proposed and investigated an ultrahigh sensitivity terahertz (THz) refractive index sensor based on four-inscribed hole defect photonic crystal structure. Due to the formation of resonant modes, the sensing properties can be obtained by shifting the sharp resonance in the transmission spectrum as changing of the analyte refractive index. In addition, the influence of structure parameters on the sensing performance is explored and demonstrated numerically. The numerical results illustrate that the Q-factor and figure of merit reach 323.71 and 167.188 can be obtained under the optimized structural parameters. In particular, an ultrahigh sensitivity of 198.8 mu m/RIU can be realized in the frequency range of 0.777-0.779 THz. The proposed sensor may find significant applications in biochemical sensing systems.Addresses:[Wen, Jin; Sun, Wei; Liang, Bozhi; He, Chenyao; Xiong, Keyu; Wu, Zhengwei; Zhang, Hui; Yu, Huimin; Wang, Qian] Xian Shiyou Univ, Sch Sci, Xian, Peoples R China; [Wen, Jin] Chinese Acad Sci, State Key Lab Transient Opt & Photon, Xian Inst Opt & Precis Mech, Xian, Peoples R China; [Wen, Jin] Xian Shiyou Univ, Sch Sci, Xian 710065, Peoples R ChinaAffiliations:Xi'an Shiyou University; State Key Laboratory of Transient Optics & Photonics; Chinese Academy of Sciences; Xi'an Institute of Optics & Precision Mechanics, CAS; Xi'an Shiyou UniversityPublication Year:2024Volume:66Issue:1DOI Link:http://dx.doi.org/10.1002/mop.33892數(shù)據(jù)庫ID（收錄號）:WOS:001068423400001 -
Record 406 of
Title:Optimization of signal-to-noise ratio of laser heterodyne radiometer
Author Full Names:Sun, Chunyan; He, Xinyu; Xu, Ruoyu; Lu, Sifan; Pan, Xueping; Bai, JinSource Title:MICROWAVE AND OPTICAL TECHNOLOGY LETTERSLanguage:EnglishDocument Type:ArticleKeywords Plus:MU-M; SPECTROMETER; SPECTROSCOPY; SENSOR; LINE; N2O; CO2Abstract:The ground-based laser heterodyne radiometer (LHR), which exhibits the advantages of small size, high spectral resolution, and easy integration, has been used for the remote sensing detection of several gases to meet a wide range of needs. This study aims to optimize the laser heterodyne system for detecting CO2 gas by focusing on existing research. Firstly, using the all-fiber laser heterodyne detection system built by our research group, the power spectrum associated with the radio frequency signals of the detection system is discussed under different conditions: under no irradiation, under sunlight only, under sunlight and laser irradiation at the absorption peak, and under a filter in the spectrum range of 185-270 MHz. Signal-to-noise ratios (SNRs) of the high-resolution spectrum have been obtained using different filter bands of 185-270, 225-270, and 225-400 MHz. Finally, the filter in the 225-270 MHz band, which has the highest SNR, is selected. Consequently, the resolution is improved and the system is further optimized. Furthermore, an optical fiber attenuator is used to change the power of the local oscillator light entering the system, and hyperspectral spectra with varying percentages of input energy and total energy are obtained. When the laser attenuation reaches 40%, the optimal SNR of the system is 486 and can be further improved to meet the expected requirements. This study will provide insights for improving the applicability of laser heterodyne technology in atmospheric sounding.Addresses:[Sun, Chunyan; He, Xinyu; Xu, Ruoyu; Lu, Sifan; Pan, Xueping; Bai, Jin] Anqing Normal Univ, Sch Math & Phys, Anqing, Peoples R China; [Sun, Chunyan] Chinese Acad Sci, State Key Lab Transient Opt & Photon, Xian, Peoples R China; [Sun, Chunyan] Chinese Acad Sci, Anhui Inst Opt & Fine Mech, Hefei, Peoples R ChinaAffiliations:Anqing Normal University; Chinese Academy of Sciences; State Key Laboratory of Transient Optics & Photonics; Chinese Academy of Sciences; Hefei Institutes of Physical Science, CAS; Anhui Institute of Optics & Fine Mechanics (AIOFM), CASPublication Year:2024Volume:66Issue:1DOI Link:http://dx.doi.org/10.1002/mop.33857數(shù)據(jù)庫ID（收錄號）:WOS:001093075800001 -
Record 407 of
Title:Dual-parameter femtosecond mode-locking pulse generation in partially shared all-polarization-maintaining fiber Y-shaped oscillator with a single saturable absorber
Author Full Names:Bai, Chen; Feng, Ye; Zhang, Weiguang; Zhang, Junying; Zhang, Tong; Mei, Chao; Liu, Pandi; Fan, Zhaojin; Qian, Jiangxiao; Yu, JiaSource Title:OPTICS AND LASER TECHNOLOGYLanguage:EnglishDocument Type:ArticleKeywords Plus:COMB; LASERAbstract:We present a design of a mode-locked fiber laser based on a polarization-maintaining (PM) Y-shaped fiber structure, which employs a single semiconductor saturable absorber mirror (SESAM) and a common polarization beam combiner (PBC) to achieve dual-parameter mode-locking femtosecond pulse in two orthogonal po-larization states. The two output pulses have different characteristics, such as repetition frequency (87.3 MHz and 91.3 MHz), average output powers (2.1 mW and 1.9 mW), pulse durations (299 fs and 377 fs) and spectral profiles (centered at 1565.6 nm and 1563.6 nm with spectral width of 9.96 nm and 9.93 nm). The properties of the two pulses are experimentally characterized and their potential applications in areas such as bistable frequency lasers and dual femtosecond optical frequency comb is discussed.Addresses:[Bai, Chen; Zhang, Weiguang; Zhang, Junying; Fan, Zhaojin; Qian, Jiangxiao; Yu, Jia] Xian Technol Univ, Sch Optoelect Engn, Xian 710021, Peoples R China; [Feng, Ye; Zhang, Tong] Chinese Acad Sci, State Key Lab Transient Opt & Photon, Xian Inst Opt & Precis Mech, Xian 710119, Peoples R China; [Mei, Chao] Chinese Acad Sci, Xian Inst Opt & Precis Mech, Dept Aircraft Opt Imaging & Measurement Technol, Xian 710119, Peoples R China; [Liu, Pandi] Xian Shiyou Univ, Sch Sci, Xian 710065, Peoples R ChinaAffiliations:Xi'an Technological University; Chinese Academy of Sciences; Xi'an Institute of Optics & Precision Mechanics, CAS; State Key Laboratory of Transient Optics & Photonics; Chinese Academy of Sciences; Xi'an Institute of Optics & Precision Mechanics, CAS; Xi'an Shiyou UniversityPublication Year:2024Volume:169Article Number:110021DOI Link:http://dx.doi.org/10.1016/j.optlastec.2023.110021數(shù)據(jù)庫ID（收錄號）:WOS:001074589200001 -
Record 408 of
Title:A neighbourhood feature-based local binary pattern for texture classification
Author Full Names:Lan, Shaokun; Li, Jie; Hu, Shiqi; Fan, Hongcheng; Pan, ZhibinSource Title:VISUAL COMPUTERLanguage:EnglishDocument Type:ArticleAbstract:The CNN framework has gained widespread attention in texture feature analysis; however, handcrafted features still remain advantageous if computational cost needs to take precedence and in cases where textures are easily extracted with few intra-class variation. Among the handcrafted features, the local binary pattern (LBP) is extensively applied for analysing texture due to its robustness and low computational complexity. However, in local difference vector, it only utilizes the sign component, resulting in unsatisfactory classification capability. To improve classification performance, most LBP variants employ multi-feature fusion. Nevertheless, this can lead to redundant and low-discriminative sub-features and high computational complexity. To address these issues, we propose the neighbourhood feature-based local binary pattern (NF-LBP). Inspired by gradient's definition, we extract the neighbourhood feature in a local region by simply using the first-order difference and 2-norm. Next, we introduce the neighbourhood feature (NF) pattern to describe intensity changes in the neighbourhood. Finally, we combine the NF pattern with the local sign component and the centre pixel component to create the NF-LBP descriptor. This approach provides better complementary texture information to traditional local sign pattern and is less sensitive to noise. Additionally, we use an adaptive local threshold in the encoding scheme. Our experimental results of classification accuracy and F1 score on five texture databases demonstrate that our proposed NF-LBP method attains outstanding texture classification performance, outperforming existing state-of-the-art approaches. Furthermore, extensive experimental results reveal that NF-LBP is strongly robust to Gaussian noise and salt-and-pepper noise.Addresses:[Lan, Shaokun; Li, Jie; Pan, Zhibin] Xi An Jiao Tong Univ, Sch Elect & Informat Engn, Xian 710049, Peoples R China; [Hu, Shiqi] AVIC Xian Flight Automatic Control Res Inst, Xian 710076, Peoples R China; [Fan, Hongcheng] Air Force Engn Univ, Inst Informat & Nav, Xian 710077, Peoples R China; [Pan, Zhibin] Chinese Acad Sci, State Key Lab Transient Opt & Photon, Xian 710119, Peoples R ChinaAffiliations:Xi'an Jiaotong University; Air Force Engineering University; State Key Laboratory of Transient Optics & Photonics; Chinese Academy of SciencesPublication Year:2024Volume:40Issue:5Start Page:3385End Page:3409DOI Link:http://dx.doi.org/10.1007/s00371-023-03041-3數(shù)據(jù)庫ID（收錄號）:WOS:001050556700001